Duplex antenna switch



Oct. 28, 1958 H. W. LEHMAN DUPLEX ANTENNA SWITCH Filed May 27, 1957INVENTOR.

HARRY W LEHMAN A T Teen/2Y8 Unite fitates DUPLEX ANTENNA SWITCHApplication May 27, 1957, Serial No. 661,715

4 Claims. (Cl. 200--5) This invention relates to switching mechanismsand more particularly to switching mechanisms especially designed toselectively connect desired coaxial lines.

A plurality of coaxial connectors such as those associated with antennasand receivers, must necessarily be selectively cross-connected atvarious times. If a pair of antennas is to be selectively connected to apair of receivers so that either antenna may be connected to eitherreceiver, some switching means is necessary. In the past, such switchingmeans have been either of the rotary type or the sliding type. Theswitching means must be a coaxial type of switch if coaxial lines arebeing used,

arent and the switch must provide adequate shielding. The rotary andsliding types of coaxial switches provide this shielding, but do so atthe expense of operating convenience and efficiency. In the coaxial typeof switch, it is a requisite that the standing wave ratio be kept withinprescribed limits and that the amount of interference between thevarious signals carried by the coaxial lines be kept at a minimum. Thisinvention provides a simple .and novel coaxial switch which effectivelymeets the above described requisites and yet provides convenience andsimplicity in operation and construction.

It is an object of this invention to provide a simple multipleconnection coaxial switch. It is a further object of this invention toprovide a coaxial switch which may interconnect a plurality of coaxialconnectors with a minimum of interference between the signals carried bythe various connectors. It is a still further object of this inventionto provide such a coaxial switch where the contacts have a desiredwiping action and the characteristic impedance of the coaxial linesconnected to the coaxial connectors at the switch is substantiallymaintained.

It is another object of this invention to provide a coaxial switch wherethe moving parts are maintained under mechanical load conditions duringthe operation period of the switch, thereby reducing possible erroneouselectrical connections due to mechanical vibrations.

These and other objects of this invention will become apparent when thefollowing description is read in conjunction with the accompanyingdrawing, in which:

Figure l is an exploded isometric view of one embodiment of thisinvention, and

Figure 2 is a sectional view of this same embodiment of this inventionthrough the plane 22.

Referring now to Figures 1 and 2, the plate 11 is composed of a sheet ofnon-conductive material having a con ductive surface aflixed to twosides thereof. This nonconductive material and the conductive surfacesafiixed thereto may be constructed in a manner such as any of thewell-known printed circuit boards having both sides plated withconductive material. On one side of the plate 11 the plating isinterrupted around a plurality of double contacts 12, 14, 16 and 18. Oneof these double contacts is individually connected to the centerconnector of one of the plurality of coaxial connectors 13, 15, 17 and19. The other contacts of the double contacts are each connected totheir related contact by a metallic strip 31. The

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contact of the double contacts which is not connected to the coaxialconnectors passes completely through the plate 11 and forms a singlecontact on the other side of the plate 11. The plating on the sidehaving the single contact is also interrupted around the single contact.

The coaxial connectors 13, 15, 17 and 19 are mounted on a metallicmember, and the center conductor of the coaxial line is passed throughthe member 32 and is electrically insulated except from the doublecontacts 12, 14, 16 and 18. The ground connection of the coaxial line iscarried to the metallic member 32, and all of the coaxial connectorshave their ground connections maintained at the same level through thismetallic member 32.

A pair of similar movable contact arm-supporting members 21 and 22 areused to support contact arms or fingers 23. These contact arm-supportingmembers are made of a non-conductive material, such astetrafiuoroethylene. The conductive contact arms 23 are attached to thesupport members 21 and 22 by any of the desired and well-known fasteningmethods. The contact arms are arranged so that each one makes contactwith a different one of the contacts 12, 14, 16 and IS in the plate 11which are not connected to the coaxial connectors.

Also, attached to these support members 21 and 22 are grounding fingers26. These grounding fingers effectively ground the contacts to theexternal members 32 and 33 and thereby reduce the cross-feed on thisswitch.

An opening 27 of a predetermined shape is cut in the plate 11 and themember 32. A third member 33 made of conductive material completes theexternal physical configuration of the switch by enclosing contactsupporting element 21. Through this opening 27 is passed a speciallydesigned piece or block 25 of non-conductive material to permit movementof the attached contact arm-supporting members only at right angles tothe surfaces of the plate 11. Both the contact supporting elements 21and 22 are connected to this specially designed block 25.

Attached to one of the contact supporting elements 21 and 22 is anon-conductive member, such as screw member 51. This member actuates themovement of the contact supporting elements at right angles to thesurfaces of the plate 11 within the limits prescribed by the block 25and the opening 27.

In operation, the relay 50 would be mechanically connected to thismember 51 so that movement of the relay would position either thecontact arm-supporting element 21 or 22 against the predetermined fixedcontact of the double contacts 12, 14, 16 and 18. Inasmuch as thecontact arms 23 on the supporting element 21 are at right angles to thecontact arms on the supporting element 22, as the member 51 is movedin-and-out, the connector 13 is connected to either the connector 15 orthe connector 17.

Thus, alternating and selective connections between the coaxialconnectors is provided. A first antenna and a second antenna, and afirst receiver and a second receiver connected to the coaxial connectors13, 15, 17 and 19 may be connected in any of the desired relationships.The movement of the contact supporting members 21 and 22 by member 51and relay 51 must be done with a predetermined force so that in eachoperative position, floating action of the switching elements isprevented. It is obvious that the dimensions of the switching, includingthe switch pieces 32 and 33, may be varied to fit a desired standingwave ratio. If such changes in dimensions cannot substantially obtainthe desired standing wave ratio, changes in pressurization and in thegrounding connections of the switch may improve the standing wave ratio.

Although this invention has been described with respect to a particularembodiment thereof, it is not to be is so limited as changes andmodifications may be made therein which are Within the full intendedscope of the invention as defined by the appended claims.

What is claimed is:

l. A switch means comprising a plate of non-conductive material, saidplate being substantially covered by conductive material on both sides,a plurality of fixed contact means extending through said plate and saidconductive side surfaces, said fixed contacts being electricallyisolated from said conductive surfaces, individual ones of said fixedcontacts electrically interconnected on a first side of said plate, aplurality of external connection means electrically connected topredetermined ones of said fixed contacts on the second side of saidplate, a plurality of movable contact supporting means, said contactsupporting means including a plurality of contact arms where the contactarms attached to a first one of said contact supporting means are atright angles to the contact arms attached to a second one of saidcontact supporting means, each of said contact arms selectivelyconnecting certain of said fixed contacts, a block of non-conductivematerial extending through said plate and said conductive surfaces, saidcontact supporting means aifixed to said block, and means for movingsaid block and said supporting means at right angles to the sides ofsaid plate whereby a selected one of said contact supporting means andsaid contact arms associated therewith are in contact with said fixedcontacts.

2. A switch means comprising a plate of non-conductive material, saidplate being substantially covered by conductive material on both sides,a plurality of fixed contact means extending through said plate and saidconductive side surfaces, said fixed contacts being electricallyisolated from said conductive surfaces, individual ones of said fixedcontacts electrically interconneted on a first side of said plate, aplurality of external connection means electrically connected topredetermined ones of said fixed contacts on the second side of saidplate, said external connection means comprising coaxial connectors, aplurality of movable contact supporting means, said contact supportingmeans including a plurality of contact arms where the contact armsattached to a first one of said contact supporting means are at right anles to the contact arms attached to a second one of said contactsupporting means, each of said contact arms selectively connectingcertain of said fixed contacts, a block of non conductive materialextending through said plate and said conductive surfaces, said contactsupporting means aflixed to said block, and means for moving said blockand said supporting means at right angles to the sides of said platewhereby a selected one of said contact supporting means and said contactarms associated therewith are in contact with said fixed contacts.

3. A switch means comprising a plate of non-conductive material, saidplate being substantially covered by conductive material on both sides,a plurality of fixed contact arms extending through said plate and saidconductive side surfaces, said fixed contacts being electricallyisolated from said conductive surfaces, individual ones of said fixedcontacts electrically interconnected on a first side of said plate, aplurality of external connection means electrically conected topredetermined ones of said fixed contacts on the second side of saidplate, said external connection means comprising coaxial connectors, theground member of said coaxial connectors being electrically connected tothe conductive surface on said first side of said plate, a plurality ofmovable contact supporting means, said contact supporting meansincluding a plurality of contact arms where the contact arms attached tofirst one of said contact supporting means are at right angles to thecontact arms attached to a second one of said contact supporting means,each of said contact arms selectively connecting certain of said fixedcontacts, a block of non-conductive material extending through saidplate and said conductive surfaces, said contact supporting meansaffixed to said block, and means for moving said block and saidsupporting means at right angles to the sides of said plate whereby aselected one of said contact supporting means and said contact armsassociated therewith are in contact with said fixed contacts.

4. A switch means comprising a plate of non-conductive material, saidplate being substantially covered by conductive material on both sides,said plate having an opening cut therein, a plurality of fixed contactmeans extending through said plate and said conductive side surfaces,said fixed contacts being electrically isolated from said conductivesurfaces, individual ones of said fixed contacts electricallyinterconnected on a first side of said plate, a plurality of externalconnection means electrically connected to predetermined ones of saidfixed contacts on the second side of said plate, said externalconnection means comprising coaxial connectors, the ground member ofsaid coaxial connectors being electrically connected to the conductivesurface of said first side of said plate, a plurality of movable contactsupporting means, said contact supporting means including a plurality offlexible contact arms where the contact arms attached to a first one ofsaid contact supporting means are at right angles to the contact armsattached to a second one of said contact supporting means, each of saidcontact arms selectively operable to connect certain of said fixedcontacts, a block of non-conductive material extending through saidplate and said conductive surfaces, said contact supporting meansaffixed to said block, and means for moving said block and saidsupporting means at right angles to the sides of said plate whereby aselected one of said contact supporting means and said contact armsassociated therewith are in contact with said fixed contacts.

References Cited in the file of this patent UNITED STATES Pi-iTENTS2,376,649 Austin May 22, 1945 2,395,870 Hiehle Mar. 5, 1946 2,759,152Charles Aug. 14, 1956 FORElGN PATENTS 263,990 Great Britain Jan. 13,1927

